Ureteric urine examination.

Uterteric urine examination can give definitive evidence of upper urinary tract carcinoma and three cases are described and illustrated. The absence of carcinoma cells in such specimens, however, does not exclude malignancy for two reasons. First, the tumours may be well differentiated and the cells not recognized at cytological examination and, secondly, carcinoma cells may not appear in ureteric urine specimens since they can be reluctant to exfoliate.